Securitizations and Variable Interest Entities (Activity in Affordable Housing Program Obligation) (Details) - USD ($)	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Securitizations And Variable Interest Entities [Abstract]
Affordable housing tax credits and other tax benefits	$ 200,000,000	$ 177,000,000	$ 144,000,000
Tax credit amortization expense recognized as a component of income tax expense	157,000,000	147,000,000	118,000,000
Affordable housing impairment	$ 0	$ 0	$ 0